1. Field of Invention
This invention relates to a process for fabricating a semiconductive device and a method of fabricating a metal-oxide-semiconductor (MOS) device.
2. Description of Related Art
With the development in the ultra-large scale IC industry, the device is gradually miniaturized, and the gate linewidth and gate dielectric thickness are gradually reduced. Silicon oxide is the most popular material for gate dielectric, but has therein pin holes easily causing electrical issues like direct tunneling current and is therefore difficult to be made into a thin gate dielectric layer.
A gate dielectric layer formed as a silicon oxide layer can be doped with nitrogen to reduce current leakage and improve the device reliability. However, the nitrogen atoms easily diffuse to the interface between the substrate and the gate dielectric layer and reduce the performance and reliability of the device.